Let say the new date is current date using getdate()
we can do this to get the date part:
convert(varchar, getdate(), 101)
we can also do this to get the time part of the old date time:
convert(varchar, datetimefield, 114)
So the idea is to concatenate the date part of a new date time with the time part of the old date time:
update table1 set datetimefield =
(convert(varchar, getdate(), 101) + ' ' + convert(varchar, datetimefield, 114))
As for the meanings of 101 and 104, refer this for more detail:
sql-convert[
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